Plastic bottles which are blow-molded are commonly used to contain a number of consumer products, including beverages. Advances in the technology of blow molding plastic bottles have allowed the bottles to be manufactured using less plastic material, resulting in lighter weight bottles which are less stable during handling and conveying.
The relevant parts of a typical blow-molded plastic bottle, as illustrated in FIG. 6, include a body portion 60, threads 58, and a neck flange 57.
Plastic bottles with circular neck flanges have been conveyed by air conveyors which have corresponding surfaces to support the neck flanges. An example of such an air conveyor is set forth in U.S. Pat. No. 4,284,370, issued to Danler et al.
The feeding and accumulation of plastic bottles presents handling and conveyance problems because of their low weight and because freshly molded bottles that are being conveyed have not completely cooled and tend to be somewhat sticky. In order to transition between one feed lane and several lanes, there must necessarily be areas where the conveyed plastic bottles are diverted from their direction of travel so that either a single lane or a plurality of lanes are thereby achieved.
Plastic bottles are very prone to binding and jamming in conveyance and accumulation equipment, especially at locations where the direction of flow of a conveyance lane is diverted. The angles or changes in direction of the flow of the plastic bottles lead to jamming and binding. Typically, the greater the angle of diversion, and the lower the weight of the plastic bottles, the more prone the conveyance system becomes to problems of this nature.
Existing conveying and accumulation machinery and methods attempt to minimize the jamming of the plastic bottles by making the transition in a series of steps wherein one conveyor may be split into two and then each of the two conveyors split into two again, and so on, until the desired number of parallel conveyors is attained. The same is true in the reverse when transition and feeding is required from several conveyor lanes to a fewer number or to a single lane conveyor.
Existing conveying and accumulation machinery and methods using the stepped means to reduce jamming require a substantial amount of floor space to achieve the desired transition. The reduced stability of the lighter weight bottles conveyed through existing conveying and accumulation machinery still results in an unacceptably high rate of jamming in the transition areas and corners due to the sudden changes in direction of the plastic bottles combined with the other factors of the bottles discussed above.
The need for effective and reliable conveying and accumulation machinery and methods has been recognized, but has not been adequately fulfilled by prior known machinery or methods.
A further need has been recognized for such conveying and accumulation machinery that greatly minimizes the jamming and consequent downtime, especially when conveying lighter weight plastic bottles.
A still further need has been recognized for such conveying and accumulation machinery which occupies far less floor space than prior known machinery and which is simpler and more reliable by the very nature of its design.
The forenamed recognized needs have not heretofore been sufficiently fulfilled by existing conveying and accumulation machinery and methods.
The present invention addresses the problems associated with existing container body air conveying equipment, particularly those problems at transition points which have been magnified by the conveying of the lighter weight plastic bottles. The present invention addresses the problems described above in a way that has the advantage of requiring substantially less floor space.
The present invention utilizes a flexible guide joint for connection to an air conveyor and a swing-arm mechanism which more reliably and effectively allows the feeding and accumulation of container bodies from one lane to several, and conversely from several lanes to one. The present invention also utilizes the flexible guide joint in combination with the swing-arm and can further utilize a second flexible guide joint at a second end of the swing-arm, such that the input to the first flexible guide joint is substantially parallel to the output of the second flexible guide joint. In addressing the forenamed problems the way this invention does, this invention has the further advantage of greater reliability in conveying the container bodies with reduced jamming and reduced equipment downtime.